The commission voted Monday to revoke Apollo Resources’ permit and ordered the site to be cleaned by October, the Bismarck Tribune (https://bit.ly/2r25dxM ) reported.

Commission records show that a state inspector observed a facility employee intentionally pumping drilling mud and wastewater onto a rancher’s pasture in October in McKenzie County, south of Williston.

Milt Madison owns the land next to the plant and said about 10 to 20 acres of his pasture have been contaminated.

“We just hope that it gets cleaned up and the land is returned to its original state so wildlife and the livestock are all safe,” Madison said.

A spill report by the North Dakota Department of Health estimates the contamination at more than 3,300 gallons (nearly 12,500 liters).

Dan Wells, the inspector who saw the dumping, said the cleanup should have taken a week. But because it wasn’t immediately done, it caused more problems in the spring.

“If they would have done it last fall when it first occurred, a lot of this would have been avoided,” he said. “Once spring thaw started, it just enlarged the area.”

Bill Suess, the spill investigation program manager for the health department, said Apollo has scraped the topsoil to remove some of the more severe contamination, but the next step is to excavate and remove the affected soil.

Suess said the agency issued the company a notice of violation and is expected to also issue a fine.

The Industrial Commission also is working on filing a civil complaint and fine, as well as the potential for criminal charges against the employee responsible for the contamination, said Lynn Helms, director of the Department of Mineral Resources.

Apollo said the employee has since been fired and the facility “stands ready to continue its efforts to clean up the site.”